[CW] Continuous Wave much better than spark

[D.J.J. Ring, Jr.]

Continuous Wave much better than spark transmissions, much narrower in
bandwidth, more efficient.

Both the Ernst Alexanderson Alternator (1904) developed by Westinghouse in
Massachusetts and used by American Marconi, later Radio Corporation of
America (1919) and Danish inventor Valdemar Poulsen's arc transmitter
(invented 1902, Lyngby, Denmark) were continuous wave emission transmission
transmitters. Dr. Reginald Fessenden, a Canadian inventor and professor of
physics took General Electric's alternator and with his own engineers in
Washington, D.C. increased the output frequency from a nominal 15 kHz to
around 67 kHz and shipped the modified alternator to the Brant Rock village
of Marshfield, Massachusetts (about a mile from where I am now.) It was
with this alternator that his company, National Electric Signaling Company
(NESCO) transmitted both continuous wave Morse and continuous wave
modulated radiotelephony with December 1906 Christmas broadcasts "... first
a short speech by me saying what we were going to do, then some phonograph
music.... Then came a violin solo by me ... which I sang one verse of, in
addition to playing the violin, though the singing, of course, was not very
good. Then came the Bible text, Glory to God in the highest and on earth
peace to men of good will, and we finally wound up by wishing them a Merry
Christmas and then saying that we proposed to broadcast again on New Year's
Eve. "

Valdemar Poulsen's arc transmitter
https://ethw.org/Milestones:Poulsen-Arc_Radio_Transmitter,_1902

Thorn Mays article on 200 kW Alexanderson Alternator
http://www.navy-radio.com/xmtrs/vlf/alexanderson-mayes-1975.pdf
https://ethw.org/Milestones:Alexanderson_Radio_Alternator,_1904

Reginald Fessenden biography https://ethw.org/Reginald_A
Fessenden Brant Rock NESCO Christmas broadcast December 1906.
https://ethw.org/Fessenden%27s_Christmas_Eve_Broadcast


73

DR
N1EA
.
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